CN102854907B - Tamper circuit based on STM32 chip - Google Patents
Tamper circuit based on STM32 chip Download PDFInfo
- Publication number
- CN102854907B CN102854907B CN201210276442.XA CN201210276442A CN102854907B CN 102854907 B CN102854907 B CN 102854907B CN 201210276442 A CN201210276442 A CN 201210276442A CN 102854907 B CN102854907 B CN 102854907B
- Authority
- CN
- China
- Prior art keywords
- tamper
- stm32 chip
- charge
- switch
- battery
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The invention provides a tamper circuit based on an STM32 chip. The tamper circuit comprises a battery, a switch and a resistor-capacitor (RC) charge-discharge circuit, wherein the battery is respectively connected with one end of the switch and a real time clock (RTC) register in the STM32 chip and supplies power for the RTC register, the other end of the switch is connected with one end of the RC charge-discharge circuit, and the other end of the RC charge-discharge circuit is connected with a TAMPER pin of the STM32 chip. According to the tamper circuit, additional chips (ICs) are not required to be added to achieve tamper functions, the tamper time is easy to control, and the tamper circuit is high in tamper sensitivity, low in cost, good in performance and interference resistance characteristics and long in service life of the battery.
Description
[technical field]
The present invention relates to electronic information field, particularly a kind of decomposing prevention circuit based on STM32 chip.
[background technology]
There is at present the terminal device of the security requirement of relating to have tamper machine function, still effective in order to ensure terminal device tamper function when the power-off, generally by button cell, RTC chip, realize, described RTC chip is the English full name of a kind of real-time clock IC(RTC: Real Time Clock, Chinese: real-time clock; IC Chinese: chip), can increase the cost of terminal device like this, and because button cell directly connects RTC chip power pin, only by connecting the decoupling capacitor of RTC supply pin, can not accurately control power supply discharge time, if discharge time is too short, vibration is fallen and is caused power supply moment to disconnect being prone to mistake lock machine, if discharge time is long, be prone to not lock machine, therefore tear the bad control of machine time of fire alarming open, be prone to lock machine or not lock machine phenomenon by mistake.
[summary of the invention]
The technical problem to be solved in the present invention, is to provide a kind of decomposing prevention circuit based on STM32 chip, and it does not need to increase extra IC and realizes tamper function, the tamper time is easy to control, tamper is highly sensitive and have noiseproof feature, and cost is low, the good and battery of performance.
The present invention is achieved in that
A kind of decomposing prevention circuit based on STM32 chip, comprise a battery, a switch and a RC charge-discharge circuit, described battery connects respectively one end of described switch and the RTC register of described STM32 chip internal, described battery is described RTC register power supply, the other end of described switch connects one end of described RC charge-discharge circuit, and the other end of described RC charge-discharge circuit connects the TAMPER pin of described STM32 chip.
Further, described RC charge-discharge circuit is to be composed in parallel successively by a capacitor C 1, a capacitor C 2 and resistance R 1 three.
Further, the capacitance of described capacitor C 1 and capacitor C 2 is 100nf, and the resistance of described resistance R 1 is 10M Ω.
Further, the described battery diode of connecting connects respectively one end of described switch and the RTC register of described STM32 chip internal again.
Further, the resistance R 2 of connecting between the other end of described switch and described RC charge-discharge circuit.
Tool of the present invention has the following advantages: the present invention controls the level of STM32 chip TAMPER pin by battery, switch and RC charge-discharge circuit, when TAMPER pin low level, the RTC data in register of STM32 chip is eliminated, thereby triggering STM32 chip reports to the police and lock machine, it realizes tamper without increasing extra chips expense, reduces equipment cost.RC charge-discharge circuit adopts large resistance to extend battery, adopts two 100nF electric capacity simultaneously, not only guarantees tamper sensitivity but also possess anti-interference function.The capacitance parameter of RC charge-discharge circuit is adjustable, by adjusting capacitance parameter, is capable of regulating discharge time, so the tamper time is easily adjusted easy to control.
[accompanying drawing explanation]
The present invention is further illustrated in conjunction with the embodiments with reference to the accompanying drawings.
Fig. 1 is the circuit diagram that the present invention is based on the decomposing prevention circuit of STM32 chip.
[embodiment]
Refer to shown in Fig. 1, a kind of decomposing prevention circuit based on STM32 chip, comprise a battery B1, a switch S 1 and a RC charge-discharge circuit, described battery B1 connects respectively one end of described switch S 1 and the RTC register of described STM32 chip internal, described battery B1 is described RTC register power supply, the other end of described switch S 1 connects one end of described RC charge-discharge circuit, and the other end of described RC charge-discharge circuit connects the TAMPER pin of described STM32 chip.Described switch S 1 is arranged under normal condition closed, run into and tear terminal device that machine situation disconnects open somewhere, for example breaking-proof switch is on mainboard, switch contact is on shell, and during terminal device normal mounting, contact withstands on breaking-proof switch, switch is closed, terminal is torn open after machine, and breaking-proof switch is left in contact, and switch disconnects.Described RTC register memory contains data.Under normal condition, switch S 1 is closure state, and described battery B1 is described RTC register power supply, and for the TAMPER pin of described STM32 chip provides a high level, simultaneously described RC charge-discharge circuit charging, keeps electric weight constant after having charged, do not recharge.When running into the abnormal conditions such as the machine of tearing open, switch S 1 disconnects, described RC charge-discharge circuit electric discharge, the TAMPER pin level of described STM32 chip is reduced to low level from high level, triggers intrusion detection feature, storage data in described RTC register are eliminated, when described STM32 chip detection is sky to described RTC register, will trigger an intrusion event and interrupt, on software, will carry out lock machine operation, as close transaction business function, terminal cannot normally be used.The present invention realizes the tamper of terminal device without extra chip expense, reduces equipment cost.
Another embodiment of the present invention is that described RC charge-discharge circuit is to be composed in parallel successively by a capacitor C 1, a capacitor C 2 and resistance R 1 three.The capacitance of described capacitor C 1 and capacitor C 2 is 100nf, and the resistance of described resistance R 1 is 10M Ω.By the resistance R 1 of 10M Ω, reduce electric current, extend battery.By the electric capacity of two 100nF in parallel, voltage is discharged to the about 1.7s of time of 1.3V by 3.3V, 1.3V voltage is that STM32 chip identification is to low level ceiling voltage, tamper sensitivity and noiseproof feature have been guaranteed, for example equipment is falling or oscillatory type, and switch S 1 moment disconnection, because the time is very short, be far smaller than 1.7s, terminal device just can not carry out false alarm or mistake lock machine.Certainly, the present embodiment only provides the parameter of one group of RC charge-discharge circuit, but the resistance R 1 of RC charge-discharge circuit, capacitor C 1, the equal capable of regulating of C2 parameter, by adjusting capacitance parameter, it it is capable of regulating discharge time, therefore the tamper time easily adjust easy to control, simultaneously by adjusting resistance R1 capable of regulating battery B1 serviceable life also.
The described battery diode D1 that connects connects respectively one end of described switch S 1 and the RTC register of described STM32 chip internal again.By this diode D1, can prevent that electric current from pouring in down a chimney battery B1.The resistance R 2 of connecting between the other end of described switch and described RC charge-discharge circuit.By this resistance R 2, electrostatic interference can be weakened and thunder and lightning disturbs, better the performance of holding circuit.
It should be noted that because the supply voltage of the RTC register of STM32 chip internal be 3.3V therefore, battery B1 adopts the button cell of 3.3V.
The present invention controls the level of STM32 chip TAMPER pin by battery, switch and RC charge-discharge circuit, when TAMPER pin low level, the RTC data in register of STM32 chip is eliminated, thereby triggering STM32 chip reports to the police and lock machine, it realizes tamper without increasing extra chips expense, reduces equipment cost.RC charge-discharge circuit adopts large resistance to extend battery, adopts two 100nF electric capacity simultaneously, not only guarantees tamper sensitivity but also possess anti-interference function.The capacitance parameter of RC charge-discharge circuit is adjustable, by adjusting capacitance parameter, is capable of regulating discharge time, so the tamper time is easily adjusted easy to control.
Although more than described the specific embodiment of the present invention; but being familiar with those skilled in the art is to be understood that; our described specific embodiment is illustrative; rather than for the restriction to scope of the present invention; those of ordinary skill in the art are in equivalent modification and the variation done according to spirit of the present invention, all should be encompassed in the scope that claim of the present invention protects.
Claims (5)
1. the decomposing prevention circuit based on STM32 chip, it is characterized in that: comprise a battery, a switch and a RC charge-discharge circuit, described battery connects respectively one end of described switch and the RTC register of described STM32 chip internal, described battery is described RTC register power supply, the other end of described switch connects one end of described RC charge-discharge circuit, and the other end of described RC charge-discharge circuit connects the TAMPER pin of described STM32 chip.
2. the decomposing prevention circuit based on STM32 chip according to claim 1, is characterized in that: described RC charge-discharge circuit is to be composed in parallel successively by a capacitor C 1, a capacitor C 2 and resistance R 1 three.
3. the decomposing prevention circuit based on STM32 chip according to claim 2, is characterized in that: the capacitance of described capacitor C 1 and capacitor C 2 is 100nf, and the resistance of described resistance R 1 is 10M Ω.
4. according to the decomposing prevention circuit based on STM32 chip described in claims 1 to 3 any one, it is characterized in that: the described battery diode of connecting connects respectively one end of described switch and the RTC register of described STM32 chip internal again.
5. according to the decomposing prevention circuit based on STM32 chip described in claims 1 to 3 any one, it is characterized in that: the resistance R 2 of connecting between the other end of described switch and described RC charge-discharge circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210276442.XA CN102854907B (en) | 2012-08-03 | 2012-08-03 | Tamper circuit based on STM32 chip |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210276442.XA CN102854907B (en) | 2012-08-03 | 2012-08-03 | Tamper circuit based on STM32 chip |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102854907A CN102854907A (en) | 2013-01-02 |
| CN102854907B true CN102854907B (en) | 2014-04-09 |
Family
ID=47401564
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210276442.XA Active CN102854907B (en) | 2012-08-03 | 2012-08-03 | Tamper circuit based on STM32 chip |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102854907B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103699857B (en) * | 2013-12-20 | 2016-07-27 | 广东威创视讯科技股份有限公司 | The anti-hacking device of electronic equipment and electronic equipment |
| CN103778727B (en) * | 2014-01-21 | 2016-09-14 | 深圳市科羽科技发展有限公司 | A kind of bank counter smart-interactive terminal |
| CN107069860A (en) * | 2017-03-31 | 2017-08-18 | 成都天奥电子股份有限公司 | A kind of energy long-time stable provides the battery of Perfect Time information |
| CN107219803B (en) * | 2017-07-27 | 2024-03-26 | 福建升腾资讯有限公司 | Device for detecting opening or closing of terminal cover in real time |
| CN111753341B (en) * | 2020-06-29 | 2023-09-22 | 广州邦讯信息系统有限公司 | Illegal disassembly detection method for Internet of things equipment |
| CN112906849B (en) * | 2021-05-06 | 2021-08-13 | 北京数盾信息科技有限公司 | Password card cover opening detection method and device and password card |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070040023A1 (en) * | 2005-08-22 | 2007-02-22 | Aj Ruggirello | Method and apparatus for protecting self service terminals from fraud and tampering |
| CN201130406Y (en) * | 2007-11-28 | 2008-10-08 | 淄博卓尔电器有限公司 | Anti-disassembling device of alarm |
| GB2457102A (en) * | 2008-02-04 | 2009-08-05 | George Schaar | Wireless intruder alarm with pressure sensor within double glazing unit |
| CN102376103B (en) * | 2010-08-17 | 2014-08-13 | 中兴通讯股份有限公司 | Anti-dismounting on-board unit and realization method thereof |
| CN102609823B (en) * | 2012-02-27 | 2015-10-28 | 深圳市华奥通通信技术有限公司 | A kind of asset management system and terminal |
| CN202771294U (en) * | 2012-08-03 | 2013-03-06 | 福建升腾资讯有限公司 | Anti-disassembly circuit based on STM32 chip |
-
2012
- 2012-08-03 CN CN201210276442.XA patent/CN102854907B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN102854907A (en) | 2013-01-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102854907B (en) | Tamper circuit based on STM32 chip | |
| KR100824828B1 (en) | Method for verifying smart battery failures by measuring input charging voltage and associated system | |
| CN102217118B (en) | Apparatus and method for protecting battery pack by sensing breakdown of sense resistor | |
| US7538519B2 (en) | Information handling system with battery protected from non-permanent failures | |
| KR20110118766A (en) | Protecting monitor circuit, battery pack, secondary battery monitor circuit and protecting circuit | |
| CN102624064A (en) | Alternating current-direct current two-level isolated direct current power device | |
| US6901520B2 (en) | Power supply protection apparatus for computer system | |
| CN202771294U (en) | Anti-disassembly circuit based on STM32 chip | |
| CN211653795U (en) | Tamper pin extension circuit and POS machine | |
| CN110569679A (en) | Cover-detaching self-destruction circuit for terminal and control method thereof | |
| US10804717B1 (en) | Resettable battery disconnect device | |
| CN106019170A (en) | Power adapter detecting device | |
| CN212965358U (en) | Broken line detection circuit with load access automatic wake-up function and power bank | |
| CN210324204U (en) | A tear lid self-destruction circuit open for terminal | |
| CN208571679U (en) | The electrostatic discharge circuit of mobile terminal | |
| CN108879587B (en) | Protection circuit and mobile terminal | |
| CN207752572U (en) | IC card detection circuit for measuring instrument | |
| CN102638028A (en) | Battery loop protection module and battery module thereof | |
| CN209282342U (en) | A kind of battery system and mobile terminal detecting state in place | |
| CN111537915A (en) | Broken string detection circuitry and treasured that charges of polymorphic type charging wire | |
| CN2865099Y (en) | Breaking protection circuit | |
| CN213637146U (en) | Chip with built-in MOS (metal oxide semiconductor) and trickle charge and circuit thereof | |
| CN105094266A (en) | Battery protection system and battery protection method | |
| CN211089223U (en) | Vehicle navigation MCU power supply circuit capable of improving power-on stability | |
| CN213780339U (en) | Broken string detection circuitry and treasured that charges of polymorphic type charging wire |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |